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Exhibit 99.1

      CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, each of the undersigned officers of Silicon
Laboratories Inc. (the "Company") hereby certify that:

(i)  the accompanying Annual Report on Form 10-K of the Company for the fiscal
year ended December 28, 2002 as filed with the Securities and Exchange
Commission (the "Report") fully complies with the requirements of Section 13(a)
or Section 15(d), as applicable, of the Securities Exchange Act of 1934; and

(ii) the information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Company.

Dated January 22, 2003


/s/ Navdeep S. Sooch
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Navdeep S. Sooch
CHAIRMAN AND
CHIEF EXECUTIVE OFFICER


/s/ Russell J. Brennan
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Russell J. Brennan
VICE PRESIDENT AND
CHIEF FINANCIAL OFFICER